1. Field of the Invention
The present invention generally relates to well intervention and more particularly to a single trip system for the placement of a bridge plug, packer or anchoring mechanism in the wellbore and for punching communication holes through the production tubing.
2. Background of the Related Art
Currently, when communication is required through the production tubing, and a sliding sleeve arrangement cannot be used, a tubing puncher is run into the desired depth. A tubing puncher is a tool which typically has a mechanical punch driven by a jarring tool or hydraulic ram. The penetration is controlled so that it punches holes in the inner tubing string without damaging the outer casing or well bore formation. This is in contrast to perforating guns. Perforating guns use an explosive charge to blast through the tubing, typically to access the formation. Their action is not controlled as the hole produced does not have defined dimensions as for a punched hole. By punching holes through the tubing string controlled circulation is achieved between the tubing and the annulus. Once the holes are punched, the tubing puncher is then retrieved from the well.
During well intervention or a work over, such hole punching requires a dedicated separate trip into the well which is both time consuming and costly. The tubing puncher trip follows the trip to install bridge plugs or packers below the desired punched hole position. Further trips are then required to provide pressure isolation or to install intervention tools such as a gas lift straddle.
A further disadvantage in this multiple run approach is in the associated inaccuracy of wireline to record the precise depth location at which the holes have been punched. As a result any tool intended to locate below the punched hole has to be run deeper into the well to ensure that it is not located over or above the punched holes. This increases the tool string length, increasing the time and cost of intervention. For tools designed to locate across the punched holes, such as a gas lift straddle, these tools must be made at great lengths to ensure the packer elements set on either side of the holes. Typical lengths can be 20 to 30 ft between packing elements. The increased tool length makes handling on the rig difficult, while the increased weight provides a greater risk of breaking the wireline during run-in.